If it took the money from someone else and "gave" it to you, it's a subsidy to you.
If doesn't take it from you in the first place, it's yours. It's not a subsidy.
I don't care what they do normally. There was a time when investment income was not taxed at all. That was never a subsidy to investors then. None of my income is a subsidy from the government. The government chooses to allow me to not count mortgage interest paid as income for tax purposes. That's not a subsidy, it's simply a choice of what they'll tax. Our representatives believed that encouraging home ownership is good for society - and that the benefit derived from that ownership pays off in other areas. Not to the gov't treasury, but to society.
For it to be given, it has to be owned in the first place. Government doesn't own anything it doesn't take from someone.